Question

The gravity is downwards why we grow height upwards

Answer 1

It is because of Atmospheric pressure

Answer 2

hormonal growth signal is then triggered in the direction of that part of the cell where amyloplasts are accumulated, i.e., the bottom. That's why roots grow downwards! In other words, plant growth hormones called auxins are produced in the roots, which cause hair root cells to grow towards gravity and water.

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